Laptop Power Jack Replacement

Repair of power connectors on laptops can vary quite a bit in price - as the work involved on various laptops varies quite a bit. Some are fairly easy to get inside and replace - a few even have the power jack on a cable that plugs in, making replacement fairly easy. Most require near total dis-assembly of the unit, and then having the right tools to un-solder the jack from the circuit board without damage and install and solder in the replacement part. Then test and re-assemble and then retest to confirm no damage or problems occurred during the dis-assemble and re-assembly. Depending on how a system is put together, and how old it is, there is always a chance of a problem due to opening a system for this level of repair. The various cables and jacks may be pulled a bit too much during dis-assembly. Screw mounts that are cracked from being dropped - can fall apart when the screw is removed.

A friend recently brought me a laptop to tear down and fix, a Dell Inspiron N5100 laptop with a bad power jack. Apparently someone bumped the power connector one time too many and shattered the center post on it. See the pictures below for a view of the jack.

This unit comes apart with what I would call a typical amount of difficulty. The power jack is on a separate board with jacks for USB and external video. However you must pretty well dis-assemble the whole unit and remove the main system board to gain access to this smaller card with the power jack on it.

Remove the battery, and the cover from the memory compartment. Remove the single screw holding the DVD drive (at the back of the drive) and slide it out.

The keyboard must come out - use a small plastic tool or flat screw driver and push gently on the 4 plastic retainers at the top edge of the keyboard - while lifting gently on the top row of keys - the top edge of the keyboard will be loose. Then slide the keyboard towards the screen a half inch or so and the tabs that hold it in place on the bottom edge will slide out. Do not lift the keyboard too much yet - as you need to locate the ribbon cable from the keyboard to the system board and dis-connect it. It has a clamp type connector - lift the little flip up flap on it then gently pull the ribbon straight out sideways.

Looking further around that area - after removing the keyboard, you will see smaller ribbon cables with clamp connectors for the power buttons, mouse pad, and such. Open them up and gently work the cables away.

Remove the 4 screws on the top silver panel - under where the keyboard was, and then the screws from the bottom of the case.

Now you can gently pry the top shell away from the bottom - working around the front and both sides. When you lift the top shell away, you can see the main system board. Remove 5 silver screws on it - marked with small triangles in white - this will dis-connect the two daughter boards and a retainer to the bottom case.

Remove the back of the top shell - and then the screen itself It has four screws holding it in place - and two small coaxial cables for the wifi-antennas (in the screen shell) and a large ribbon cable for the screen itself. The small coax connectors can be gently pulled straight up if you grip them and rock slightly as you pull. Try not to tip them very far as you remove them until dis-engaged from the mating connectors. Once dis-connected it should lift straight up and out. Watch for cracked or broken mounting posts for the screen hinges - if the screws get loose, the pressure of the screen rocking back and forth can damage these so easy. This particular unit has some severe damage to the right side hinge - see the pictures for details. I have pictures of the left side hinge mount and its posts, and the right side and whats left of the right side posts. Sometimes if they are just cracked you can use epoxy glue and some reinforcement material to fix, but when they are this bad - it is often difficult to fix.

The left side of this one was ok - See the next two pics of the hinge and the posts they mount to.

The two pictures below show the right side hinge area was damaged. The plastic posts have shattered, leaving the threaded parts still on the screws and the plastic posts pretty much gone.

This system has 5 screws on the top of the system board, 4 holding the two daughter boards and one toward the front right to hold the board in. Remove these 5 screws and then lift the main circuit board - carefully jiggle the two daughter cards loose as you do.

Check the picture to the left and you will see one other post on this unit - was broken completely loose - if you look at this pic you will see its broken away and laying up higher on the case floor. This type of damage is usually from the laptop being dropped.

Then you can get the smaller circuit board out - so you can examine it and remove the jack that is bad. Use a magnifying glass or jeweler's loupe - to look carefully for stress cracks and broken solder joints. If your particular jack is not physically damaged, but works only when you hold the power cord and plug a certain way - you may just have a poor solder connection or crack in the board. A bit of soldering work should fix either of these common problems. If the board is cracked, you can use a hobby knife to scrape away the colored coating over the broken trace until copper shows on both sides of the crack. Then solder a short length of wire across the two sides of the crack - repairing the damage.

The original jack on this laptop was damaged physically - see the picture to the left and you will see the new part on the right side - and the board with old jack in the center and left of the picture. If the jack is damaged, as this one is, you will need to remove the part and install a new one - or possibly replace the board as a unit if its a small card like this one uses.

The picture to the right shows bottom of the board with the old part still soldered in. This is not the simple twist a wire together and melt solder on it kind of repair. If you are not familiar with how to do this type of work - find some other piece of gear to practice on first - rather than trash your board for the laptop. Or if its one like this where you can order a separate board already together for not too much more than the part by itself, save yourself the bother if you are not comfortable with soldering. If your power socket is directly on the laptops main circuit board, you will have to do the work. Of course - if you have someone who can do it for you - take the board (in an anti-static bag for safe handling) to that person for help - at least you will save the money it would have cost to dis-assemble the laptop to get to the area you need.

To desolder the bad part, you need good quality soldering gear - preferably a vacuum desoldering iron with digital temperature control and more than a bit of skill and experience. You could use a less expensive iron and the desoldering braid we call SOLDER WICK - as it attracts solder when heated. I won't go into all the steps you need to follow to do this work - they are covered elsewhere, but please realize these boards are not easy to work with if you are not experienced. They have multiple layers and the paths are easy to damage - especially when you start yanking on a part trying to remove it without making sure every pin is totally clean and moving free after desoldering.

Suffice it to say you will need to remove the old solder, loosen the pins and then lift the old jack away. Then clean the holes by putting some fresh solder in each and then removing it. Then clean the board and solder area with a spray cleaner and an old toothbrush, or use some high test alcohol - wood or 80% isoprophyl to clean. Only use what you have to - and watch for any that gets away - some parts - especially plastics - will fog up or be damaged by these liquids.

See the next pictures to the right to see both sides of the board after de-soldering and cleaning.

Once you have the holes clean, put the new jack in - watching for it to be level and at the same height and position as the original. It helps to take a picture of the original and have it to compare with as you insert and solder the new part in. I usually lightly tack on or two pins and check for proper alignment - while its easy to heat up one pin and adjust. When you are satisfied with the positioning go ahead and finish soldering it in - then clean the solder area lightly as needed.

See the pictures to the left to see the bottom and top side of board after new part is soldered in.

Eyeball the new solder work to make sure you have not bridged the solder across two points that should not be connected.

In general use only as much solder as needed to fill in the gaps. Remove any excess with the vacuum de-soldering tool or solder wick.

Trial fit a charging plug into to it to be sure that all fits well. Re-assemble the system and test again to be sure all is working. Every time you tear down a system you run a risk of something coming apart or being damaged.